The main purpose of this essay is to show that Kant's account of the nature of mathematical thinking is still highly relevant to the philosophy of mathematics. For Kant has raised important questions which, whether or not one agrees with his answers, must be answered if the nature of pure mathematics and of its application to empirical phenomena is to be understood. The essay begins with a brief summary of Kant's position, with special emphasis on those of his theses which are still regarded as central by contemporary mathematicians and philosophers (§1). There follows a discussion of some postKantian developments and reactions to Kant's philosophy of mathematics (§2). The essay ends with an outline of an alternative view of the structure and function of pure and applied mathematics (§3).